Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Snapshots differentiate molecules from their mirror image

29.11.2013
Max Planck researchers are able to reveal the spatial structure of chiral molecules

Small difference, large effect: Most biological molecules occur in two variants, an original and its mirror image. As a result, they are related to one another like the left hand to the right.


Molecular mirror images of, so-called enantiomeres, of dideuterooxirane (grey: hydrogen, green: deuterium, blue: carbon, red: oxygen).

© Rupprecht-Karls-University Heidelberg/O.Trapp


A combination of mass spectrometry and subsequent Coloumb explosion enables an analysis of the chirality of molecules, in this case oxirane.

© Herwig, Zawatzky, Wolf, Trapp, Kreckel

For instance, the left- and right-handed variant of the same molecule makes lemons smell different from oranges. This so-called chirality also plays an important role in pharmaceutical research.

Working in close collaboration, physicists from the Max Planck Institute for Nuclear Physics and chemists from Heidelberg University have now developed a method which, so to speak, takes a snapshot of chiral molecules and so reveals their spatial atomic structure. The molecule's handedness, or chirality, can be directly derived from this information.

Many biological processes are entirely dependent on whether the participating organic molecules are left- or right-handed. Researchers refer to molecules which occur in two forms that are the mirror image of one another as "chiral" molecules. Scientists would therefore like to know how the atoms are arranged relative to one another in such molecules. In scientific jargon this is known as the absolute configuration, and it can be used to identify the molecule's handedness.

While methods for determining the handedness of chiral molecules are indeed available, they do not reveal the absolute configuration without making use of theoretical models. Moreover, no measurement method has previously been available which is capable of investigating the handedness of individual chiral molecules in the gaseous state. The researchers working with Holger Kreckel and Andreas Wolf of the Max Planck Institute for Nuclear Physics and Oliver Trapp from the Institute of Organic Chemistry at the University of Heidelberg have, for the first time, been able to determine the sense of handedness, or chirality, of a gaseous sample, a chiral epoxide, by directly imaging its molecular structure.

To this effect, Trapp's team of chemists firstly produced a compound with defined handedness by transferring the handedness of a derivative of naturally occurring tartaric acid onto the target molecule dideuterooxirane. Kreckel and his team then carried out their measurements using minuscule quantities of this substance in highly dilute concentrations.

The team at the Max Planck Institute for Nuclear Physics took the electrically neutral molecules and produced ions with a single positive charge by removing a single electron from each molecule. These ions can be boosted to very high speeds in a particle accelerator. The accelerated ions then pass through a very thin diamond foil. In under one femtosecond (one millionth of a billionth of a second), the foil strips the binding electrons from the molecules. All that remains are highly charged atoms which vehemently repel one another. Having lost the electrons that "glue" the molecules together, the fragments now fly apart.

After passing through the foil, the fragments move further apart from one another. However, the atoms retain their relative positions. As the time of flight increases, an ever larger, three-dimensional image of the molecule, retaining the underlying geometry, is obtained. Once it reaches a 3D detector, the image of the molecule has already grown to a few centimetres in size, and the detector records this structure. In order to meet the demanding requirements which apply to measuring chiral molecules, the detector arrangement was optimised to detect up to five fragments at once. The image on the detector shows the absolute configuration which in turn directly reveals the molecule's handedness. The pioneering work for this multiparticle "Coulomb Explosion” detection scheme was carried out at the Weizmann Institute in Israel.

"The way the experiment is set up, it would also permit the investigation of chiral fragments of molecules", explain the researchers. This is because, in the described experiment, a mass-selective filter upstream of the diamond foil selects molecule fragments of a desired mass. The filter can be adjusted such that only the chiral fragment of interest is directed onto the foil and is thus recorded by the detector. It is precisely this combination of mass spectrometry with a Coulomb explosion measurement that the researchers believe will be attractive to future applications with chiral molecules.

In future, the Heidelberg-based researchers are hoping to expand their expertise in detecting the handedness of chiral molecules. They already have their eyes on another method in which the chiral molecules are accumulated in an ion storage device prior to the Coulomb explosion.

Contact

Dr. Holger Kreckel
Max Planck Institute for Nuclear Physics, Heidelberg
Phone: +49 6221 516-517
Email:holger.kreckel@mpi-hd.mpg.de
PD Dr. Bernold Feuerstein
Press Officer
Max Planck Institute for Nuclear Physics, Heidelberg
Phone: +49 6221 516-281
Email:info@mpi-hd.mpg.de
Original publication
Philipp Herwig, Kerstin Zawatzky, Manfred Grieser, Oded Heber, Brandon Jordon-Thaden, Claude Krantz, Oldrich Novotný, Roland Repnow, Volker Schurig, Dirk Schwalm, Zeev Vager, Andreas Wolf, Oliver Trapp, Holger Kreckel
Imaging the absolute configuration of a chiral epoxide in the gas phase
Science, 29 November 2013

Dr. Holger Kreckel | Max-Planck-Institute
Further information:
http://www.mpg.de/7634710/coulomb-explosion-method

More articles from Life Sciences:

nachricht Switch-in-a-cell electrifies life
18.12.2018 | Rice University

nachricht Plant biologists identify mechanism behind transition from insect to wind pollination
18.12.2018 | University of Toronto

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Data storage using individual molecules

Researchers from the University of Basel have reported a new method that allows the physical state of just a few atoms or molecules within a network to be controlled. It is based on the spontaneous self-organization of molecules into extensive networks with pores about one nanometer in size. In the journal ‘small’, the physicists reported on their investigations, which could be of particular importance for the development of new storage devices.

Around the world, researchers are attempting to shrink data storage devices to achieve as large a storage capacity in as small a space as possible. In almost...

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Pressure tuned magnetism paves the way for novel electronic devices

18.12.2018 | Materials Sciences

New type of low-energy nanolaser that shines in all directions

18.12.2018 | Physics and Astronomy

NASA research reveals Saturn is losing its rings at 'worst-case-scenario' rate

18.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>